The OEM wheels, both steel and alloy have 4.5 inches backspacing and are "0" offset. Wheels with less backspacing can be used to "widen" the stance of the vehicle. Excercise caution as this can lead to fender/tire clearance issues with the suspension compressed.
I've run 13" wide 36's on the factory steel - no issues. Any wider though, like the true 13.5 iroks, and problems can arise quick, so def a brilliant idea to stay with the 4.5.
If ya wanted alloys, I'd say check the classifieds below, but you said steel. If ya need center caps for the steel's - I gotta set laying around too. Don't know why I ever bought those things. :whoops:
Thanks, guys. We're crrently running the OEM alloys (my '97 is the same color/40th as Junk's ) and want to put a set of trail tires on some steelies for the one trip a year we will wheel it. (I have a 40 that is a dedicated trail truck. ) I'll stick with OEM specs and go 16x8 with 4.5 b/s and "0" offset.
If you are going with dedicated trail tires, I would go wider, especially if the truck is lifted. Deal with the rubbing, but having the stance wider does wonders on the trail. Not only is it more stable on side hills but it keeps your body of the rocks as well. Rule of thumb is to go wider 1" in stance for every 2" you go up.
My 80 has wheels at that has 1.25" less backspacing each, and they are 10" wheels. Over track is 6.5" wider than stock.